#include<bits/stdc++.h>
//#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math")
//#pragma GCC optimize(2)
//#pragma GCC optimize(3)
//#pragma GCC optimize("Ofast,unroll-loops")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4.1,sse4.2,avx,avx2,popcnt,tune=native")
//#include <immintrin.h>
//#include <emmintrin.h>
#define int long long
#define ls(x) ((x)*2)
#define rs(x) ((x)*2+1)
#define fi first
#define se second
#define pii pair<int,int>
#define Debug(...) fprintf(stderr, __VA_ARGS__)
#define For(i,a,b) for(int i=a,i##end=b;i<=i##end;i++)
#define Rof(i,a,b) for(int i=a,i##end=b;i>=i##end;i--)
#define rep(i,  b) for(int i=1,i##end=b;i<=i##end;i++)
using namespace std;
const int N=1e6+5,base=999983,Mod=998244353;
//char buf[(1<<21)+5],*p1,*p2;
//#define getchar() (p1==p2&&(p2=(p1=buf)+fread(buf,1,1<<21,stdin),p1==p2)?EOF:*p1++)
inline void chmx(int &x,int y){(x<y)&&(x=y);}
inline void chmn(int &x,int y){(x>y)&&(x=y);}
inline void Add(int &x,int y){(x=x+y+Mod)%=Mod;}
inline int read(){
	int f=0,x=0;
	char ch=getchar();
	while(!isdigit(ch)){f|=(ch=='-');ch=getchar();}
	while(isdigit(ch)){x=(x<<3)+(x<<1)+(ch^48);ch=getchar();}
	return f?-x:x;
}
void print(int n){
    if(n<0){
        putchar('-');
        n*=-1;
    }
    if(n>9) print(n/10);
    putchar(n%10+'0');
}
int id,n; 
int a[N],ans;
vector<int>q[N];
bool vis[N];
int dep[N],rt;
void getrt(int x,int faz){
	dep[x]=dep[faz]+1;
	for(auto y:q[x]){
		if(vis[y]||y==faz) continue;
		getrt(y,x);
	}
	if(dep[x]>dep[rt]) rt=x;
}int mxd[N];
void dfs(int x,int faz){
	dep[x]=dep[faz]+1;mxd[x]=dep[x];
	for(auto v:q[x]){
		if(v==faz) continue;
		dfs(v,x);
		mxd[x]=max(mxd[x],mxd[v]);
	}
}
signed main(){
	freopen("forest.in","r",stdin);
	freopen("forest.out","w",stdout);
	// ios::sync_with_stdio(false);
	// cin.tie(0); cout.tie(0);
	id=read(),n=read();
	int lst=0;
	if(n<=500){
		For(i,1,n-1){
			int x=read()^ans;
			q[x].push_back(i+1);
			q[i+1].push_back(x);
			ans=0;
			dfs(1,0);
			For(j,1,i) mxd[j]-=dep[j];
			For(j,0,i)if(j!=1){
				vis[j]=1;rt=0;
				getrt(1,0);
				int p=rt;rt=0;
				getrt(p,0);
				ans=max(ans,dep[rt]+mxd[j]-1);
				vis[j]=0; 
			}
			printf("%lld\n",ans);
		}
		return 0;
	} 
	For(i,1,n-1){
		int x=read()^ans;
		q[x].push_back(i+1);
		q[i+1].push_back(x);
		dep[i+1]=dep[x]+1;
		ans=max(ans,dep[i+1]);
		printf("%lld\n",ans);
	}
#ifdef LOCAL
    Debug("\nMy Time: %.3lfms\n", (double)clock() / CLOCKS_PER_SEC);
#endif
	return 0;
}

